CIRCE’s optical bench
Canarias InfRAreD CameraExperiment
GTC Observing Guide
S. Nicholas Raines, Stephen S. Eikenberry, Craig D. Warner, AlanGarner, Richard Deno Stelter
On behalf of the CIRCE team
2015-06-12
circe_110_001_gtc_obs_guide
Processed: 2015-06-12 at 12:26
hg tag 1.A for changeset
Colophon
Comment About Printing
This document’s native paper size is ISO 216 A4. However, the margins are set such thatthe document may be printed to US letter paper with 100% scaling (Page Scaling = Nonein Adobe Reader); the Auto-Rotate and Center probably should not be enabled, butplay with it.
Please print at full scale for both paper sizes for best legibility!There should be 22 pages (plus front matter).
Document Construction Information
This document was created with pdflatex, available in current up-to-date latex distribu-tions (specifically TexLive). The memoir document class was used; this class provides anumber of carefully-designed document structures. Examples in the class manual showedhow to produce a document which should fit on both US Letter and A4 papers.
This PDF compiled by pdfLATEX version: 140, revision 13.LATEX version: LATEX 2ε 2011/06/27.
Tracking information
The files for this document are tracked with Mercurial, and the currently assigned tagshould be on the cover page.
Mercurial hgtag: 1.A for changeset .
Full Contents
Full Contents iii
Executive Summary v
Contact Information vii
Revisions ix
Acronyms, Abbreviations, and Terms xi
1 CIRCE Overview 1
2 Bringing up the CIRCE software at the GTC 32.1 Log into ormcon4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Starting the agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.3 Starting the GUIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.4 Initialize ufcjec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5 Verify the GTC software is running . . . . . . . . . . . . . . . . . . . . . . . . 7
2.6 Restarting or shutting down the software . . . . . . . . . . . . . . . . . . . . 8
2.6.1 Closing the GUIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.6.2 Restarting the temperature or pressure agents . . . . . . . . . . . . 9
2.6.3 Restarting all of the agents . . . . . . . . . . . . . . . . . . . . . . . . 10
2.6.4 Restarting the motor agent or the DAS . . . . . . . . . . . . . . . . . 10
2.6.5 Stopping the agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 Running CIRCE at the GTC 113.1 Read the mechanism positions . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 Datum the mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3 Taking images . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.3.1 Acquiring single images . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.3.2 Acquiring images using Observing Sequence files . . . . . . . . . . 14
3.4 Focusing CIRCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.5 Using the Telescope Offset Control panel in JDD . . . . . . . . . . . . . . . . 14
4 Daily actions with CIRCE 174.1 Dome closed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
iii
Full Contents
4.2 End of night tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.3 Useful reference information . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
5 CIRCE Trouble Shooting 195.1 General Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6 Mechanism Operational Parameters Details 216.1 Window Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.1.1 Nominal mechanism indexer parameters . . . . . . . . . . . . . . . 21
iv / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
Executive Summary
This document will list and describe basic commands for observing with CIRCE.
v
Contact Information
The name, title, address, telephone number, fax number, and email address of the princi-pal contact for CIRCE is:
Prof. Steve S. EikenberryMIRADAS Principal InvestigatorUniversity of FloridaDepartment of AstronomyP.O. Box 112055
211 Bryant Space Science CenterGainesville, FL 32611-2055 USA
00+1+352-294-1833 (direct)00+1+352-294-1870 (Department Main Office)[email protected]@ufl.edu
vii
Revisions
Tag Who Date Description
1.A S. N. Raines 2015-06-12 Added window mechanism info from SSE in newchapter.Added Colophon, Acronyms, and Revisions.
«None» R. D. Stelter 2015-03-10 UpdatesNew center of RotAdded details from maintenance doc.
«None» S. N. Raines 2014-12-11 to2015-02-03
Other updates
«None» S. N. Raines 2014-12-11 New hg repository.Revisions — Concluded
Notes
The files for this document are tracked with Mercurial.
ix
Acronyms, Abbreviations, and Terms
ADU Analog Data UnitsAPI Application Programming Interfaces
ASIC Application Specific Integrated CircuitCIRCE Canarias InfRAreD Camera Experiment
CIS CIRCE Interface ServerCJEC CIRCE Java Engineering ConsoleCoG Center of GravityDAS Data Acquisition ServerETC Exposure Time Calculator (see ITC)
FC Folded CassegrainFITS Flexible Image Transport SystemFOV Field of ViewFPA Focal Plane Array
FWHM Full Width at Half MaximumGCS GTC Control System
CORBA Common Object Request Broker ArchitectureGTC Gran Telescopio CanariasGUI Graphical User Interface, e.g. the Inspector
H2RG HAWAII-2RGHgCdTe Mercury Cadmium Telluride, an alloy of CdTe and HgTe
IDL Interface Definition LanguageI-SDEC IUCAA SIDECAR Drive Electronics Card
ITC Integration Time Calculator (see ETC)IUCAA Inter-University Centre for Astronomy and Astrophysics
JDD Java Display DeviceLCU Local Control Unit (a computer host)LN2 Liquid Nitrogen
MEF Multi-Extension FITSMOC Module of Optical ControlN.A. Not ApplicableNGS Natural Guide StarNIR Near Infrared
OMs Observing ModesPSF Point Spread Function
ROIC Read-Out Integrated Circuit
xi
Acronyms, Abbreviations, and Terms
SIDECAR System for Image Digitization Enhancement Control and RetrievalTCS Telescope Control SystemTIS Telescope Information ServerUF University of Florida
WCS World Coordinates System
xii / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
1 CIRCE Overview
CIRCE is the Canarias InfRAreD Camera Experiment. It is comprised of a single largeLiquid Nitrogen-cooled Dewar, designed to be mounted to the GTC Folded CassegrainRotator. It is primarily a Near Infrared (NIR) imager, with polarimetry capabilities. TheDewar contains all of the powered optics, filters, stops, and the detector array; at somefuture date it will contain prisms for spectroscopy. A functional diagram will be includedat a later date. A brief listing of important parameters is given.
Array: Teledyne HAWAII-2RG 2048×2048 pixel controlled by a cryogenic SIDECAR ASIC.Thirty (30) of the thirty-two (32) array amplifiers are active.
Array Interface: An Inter-University Centre for Astronomy and Astrophysics (IUCAA)I-SDEC ASIC to USB interface.
Linearity:
0.5% non-linear at XX,000 ADU
2.0% non-linear at YY,000 ADU
> 3.5% non-linear at ZZ,000 ADU
Plate Scale: 0.1 arcsec/pixel
Field of View: ∼ 200 arcsec×190 arcsec
Detector Characteristics
Full Well = XX, 000 ADU
Target Count Level = YY, 000– ZZ, 000 ADU
CDS Read Noise = NN e−
Gain = GG e−/ADU
Filters J, H, Ks
Linear Polarimetry A Half Wave Plate (HWP) insertable into the beam at the GTC focusand a Wollaston prism within the collimated beam.
Mechanisms To the observer there is one filter mechanism and one polarimetry mecha-nism. In reality the filter mechanism is comprised of three different filter wheels, aLyot wheel, and a Grism wheel. Filter Wheel 1 (FW1) contains the NIR filters anda Dark, and the other filter wheels are empty. The Lyot wheel contains a stop forthe GTC and two Hartmann masks for engineering. The Grism wheel presently(2014-12-11) contains the Wollaston prism for polarimetry.
1
1. CIRCE Overview
Instrument Control The circe account on the GTC hosts runs the instrument GUIs, andcommunicate with the circelcu host within the CIRCE Electronics rack mountedon the Elevation Ring.
Data Acquisition and Storage As noted above, data from the array are streamed fromthe ASIC through the I-SDEC controller to circelcu. Data are transferred to theGTC data archive. Data will periodically (weekly or daily) need to be removed from thecircelcu disk.
2 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
2 Bringing up the CIRCE software at theGTC
CIRCE is presently controlled from two custom Java GUIS, ufcjec (UF CIRCE JavaEngineering Console), and ufjdd (the CIRCE Java Display Device). These tools can loadPhase II-generated observing script XML files. The GUIs talk to the CIRCE instrumentcontrol computer, circelcu, which runs all of the software agents that actually controlthe instrument. This is schematically illustrated in a software deployment diagram inFigure 2.1 (below).
2.1 Log into ormcon4
CIRCE may be operated from any of the GTC computer hosts (e.g. devcon8, or ormcon4)under the circe account.
1. In the control room, log onto ormcon4 as circe. If logged in as another user, use
circe@ormcon4:> ssh circe@localhost
2. Ensure the shell is tcsh
«circelcu »
Executive AgentLakeshore AgentVacuum AgentCISDAS
Local data
« ormcon4 »
CJECJDD
«ormserver5 »
TIS
«Data archive »
Figure 2.1. The observer runs interface software on ormcon4 and software agents on circelcu; theseagents interface with the Telescope Information server on ormserver5, and sends data to the GTC dataarchive.
3
2. Bringing up the CIRCE software at the GTC
circe@ormcon4:> tcsh
2.2 Starting the agents
A number of software agents act as interfaces between the high level user interface GUIsand the actual hardware; they includeExecutive This is a top level agent that keeps track of everything.
Environmental These include
Pressure This agent talks to the Pfeiffer vacuum gauge, and monitors the currentDewar pressure.
Temperature This one agent that talks to two devices, the LakeShore 218 8-channeltemperature monitor, and the LakeShore 331 2-channel temperature monitorand controller associated with the detector control and readout system.
Motor This communicates with the mechanism motion control motors.
CIS This is the CIRCE Interface Server; the DAS uses this to talk to the TCS (TelescopeControl System).
DAS This is the data acquisition server. Images taken with CIRCE are written to thecircelcu host, and the DAS sends the data to the GTC data archive.
These are run on circelcu, and this sequence assumes the instrument is fully up andrunning for operation.
1. Log onto circelcu
ssh circe@circelcu
Do not use the -X or -Y options to ssh; we had weird X errors during engineeringcommissioning and X-forwarding is not required here.
2. Start the Executive and environmental (pressure, temperature) agents and beginlogging
circe@circelcu:> ufcircestart -preset default1.
3. Start the motor agents, DAS, and CIS
circe@circelcu:> ufrestart mc
circe@circelcu:> ufrestart das
circe@circelcu:> ufrestart cis
N.B. When the DAS starts it will automatically do an Init & Config Sidecar.
2.3 Starting the GUIs
An outline of the steps to startup the CIRCE GUIs from the GTC control room is given here.The ormcon4 workstation contains four (4) monitors, ormcon4:0.1 to ormcon4:0.4;from the terminal you can launch a new window on one of the other displays by firstexecuting setenv DISPLAY ormcon4:0.1, for example.
1.circe@circelcu:> ufcircestart -preset list will list several preset options, i.e. sim331 incases where a mode other than the default is required.
4 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
2.3. Starting the GUIs
Figure 2.2. The main CJEC main tab is shown, and the Health is GOOD, and the Status isIDLE for the ExecutiveAgent, LakeshoreAgent, VacAgent, and circeDAS.
1. Log onto ormcon4 as circe. If logged in as another user, use
ssh circe@localhost
2. Start tcsh
circe@ormcon4:> tcsh
3. Start ufcjec with2
circe@ormcon4:> ufcjec -host circelcu -tcshost ormserver5
This will launch a single window (Figure 2.2, page 5).
4. Start ufjdd with
circe@ormcon4:> ufjdd -host circelcu
This will launch two (2) windows (Figure 2.3, page 6).
2. The default TCS port value is -tcsport 12008.
circe_110_001_gtc_obs_guide; hg tag: 1.A 5 / 22
2. Bringing up the CIRCE software at the GTC
Figure 2.3. The two windows of JDD are shown. Top: This window displays the full image from CIRCE.The image may be displayed with different scale factors. It has two buffers, called Src and Bgd, and candisplay either one or their difference. Bottom: This window shows subregions of the Full Display window.Single exposures may be initiated here, and an exposure’s status and progress may be followed (bottom left).
6 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
2.4. Initialize ufcjec
Table 2.1. CIRCE Normal Ranges. Note that Ch 1 is attached to the vacuum jacket and should be within4 Kelvin of the dome ambient.
Pressures (Torr) Temperatures (K)
Pfeiffer LakeShore 218
Normal 5× 10-7 to 2× 10
-7 Ch 1 274±10OK < 5× 10
6 Ch 2 100±10Ch 3 105±10
Ch 4, 5, 6, and 7 86±5Ch 8 95±10
If out of range contact LakeShore 331
Steve Eikenberry Ch A Muertotelfono: +1 352 514 7632 (no conneción)24 horas, 7 dias Ch B 82±4
2.4 Initialize ufcjec
The GUI will start up on the CJEC Main tab (Figure 2.2, page 5), which will show thestatus of the ExecutiveAgent, LakeshoreAgent, VacAgent, and circeDAS3. Thesystem will be ready once all of their fields say
HEALTH: GOODSTATUS: IDLE
Note, the ExecutiveAgent will take 30– 40 s before reaching this state, upon initialstartup, as it takes that long to communicate with the Baytech remote AC power control.In the event that the buttons on CJEC are in a disabled state due to an error, they may allbe enabled or disabled under Options pulldown menu at the top left. The log may alsobe viewed.
Once the agents are ready, it is also a good idea to see if the temperature and pressurereadings are at good values; these are tabulated in Table 2.1 (page 7). Ten (10) temperaturereadings are shown in the green sub-region on the left of the main tab, and all of the valuesexcluding LS218CH1 should be < 110 K. A strip chart of the LakeShore 218 temperaturevalues may be examined in Figure 2.4 (page 8). The pressure reading is shown on theVac tab4 (cf. Figure 2.5, page 9), which also has a strip chart; the normal range should be5× 10−7– 2× 10−7 Torr (cf. Table 2.1).
The Detector Control parameters are set in the top right light-blue region on theCJEC Main tab. It is a good idea to press the yellow Check Sidecar Status buttonafter bringing up CJEC.
2.5 Verify the GTC software is running
The CIRCE telescope information server (TIS; or CIRCETelescopeServer) must be runningon some GTC host, in order to obtain correct FITS header information, and for the data
3. A present the status of the CIS is not shown4. The pressure shown in the figure is 3.2× 10−3 Torr.
circe_110_001_gtc_obs_guide; hg tag: 1.A 7 / 22
2. Bringing up the CIRCE software at the GTC
Figure 2.4. The CJEC Temperatures tab shows a strip chart of recent temperature values. Different channelsmay be displayed, and regions may be examined by holding down the left mouse button and selecting arectangular region within the strip chart.
to be moved into the data archive. Note, the data will always be written to \data oncircelcu, which also has an NFSmount point to orm-scidb. To verify,
1. Select the CJEC TIS tab and press the Update button. The RA and Dec text valueson the tab should update to match the present telescope position.
2. Also, examine the file circe@circelcu:> \log.CIS for connection error mes-sages (e.g. grep ERROR).
2.6 Restarting or shutting down the software
If the Dewar is under vacuum and at any temperature below ambient, the agents shall be keptrunning. This is so that the instrument’s health can be monitored at any time. However,while the instrument is in use it is sometimes necessary to stop and restart the agents.
2.6.1 Closing the GUIs
It is always possible to quit the GUI interfaces, simply by closing their windows.
8 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
2.6. Restarting or shutting down the software
Figure 2.5. The CJEC Vac tab shows a strip chart of recent pressure values, and the Pressure 1 entryon the left shows the numerical pressure reading inTorr.
2.6.2 Restarting the temperature or pressure agents
It is the Executive agent which restarts the temperature and pressure agents; n.b. itcannot not restart the motors or DAS. This should be done from ufcjec, on the tablabeled Executive (Figure 2.6, page 10). Use the pulldown menu in the top right of thetab to select the agent(s) to reboot, then press the Reboot Agent(s) button.
Note, circe@circelcu:> ufcircestop -h will list the syntax for stopping eitheragent from the command line.
1. First stop the agent
circe@circelcu:> ufcircestop ufVac orcirce@circelcu:> ufcircestop ufcirceLakeshore
2. Then restart the agent
circe@circelcu:> ufcircestart ufVac orcirce@circelcu:> ufcircestart ufcirceLakeshore
Alternatively, stop and restart the agent all in one command:1. circe@circelcu:> ufrestart ufVac or
2. circe@circelcu:> ufrestart ufcirceLakeshore.
circe_110_001_gtc_obs_guide; hg tag: 1.A 9 / 22
2. Bringing up the CIRCE software at the GTC
Figure 2.6. The CJEC Executive tab shows rebootable agents in the top section of the panel. The left side isan interface to the Baytech power outlet controller.
2.6.3 Restarting all of the agents
1. Log onto circelcu
ssh circe@circelcu
2. circe@circelcu:> ufrestart -preset
2.6.4 Restarting the motor agent or the DAS
1. Log onto circelcu
ssh circe@circelcu
2. circe@circelcu:> ufrestart mc
3. circe@circelcu:> ufrestart das
2.6.5 Stopping the agents
To stop all of the agents from circelcu
1. circe@circelcu:> ufcircestop -a
10 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
3 Running CIRCE at the GTC
The CJEC Main tab will probably be the most used interface for loading observing scripts,along with the CIRCE Java Data Display’s (JDD) two windows. However, after starting thesoftware the instrument’s current configuration should be verified on the CJEC Motorstab (Figure 3.1, page 12).
3.1 Read the mechanism positions
In general use, CIRCE mechanism positions will be controlled via Phase II-generatedObserving Scripts; in this case the CJEC Motors tab should be used display the currentpositions. The CJEC Motors tab may be used to Datum or Move the mechanisms, butthis should only be used by experienced CIRCE users. The mechanism’s names, and associatedindexers are listed in the column second from right labeled Mech Name. Each name hasan associated check box, which enables the associated Abort, Datum, or Move buttons,and the corresponding Named Position pull-down menu. The mechanisms are
A> Window,
B> HWPRot (the Half Wave Plate Rotator),
C> LinSlide (the linear slide, which carries the HWP),
D> FW1
E> FW3⇒ This mechanism should not be moved, as of 2014-12-11.
F> FW2
G> LW (the Lyot wheel)
H> GW (the Grism wheel, which also carries the Wollaston prism for polarimetry).
As can be seen from the list, CIRCE has three separate wheels for filters, but the Phase IIobserving scripts treat them as one unified Filter Wheel.
After starting all of the agents it is good to query their positions.
1. Select the CJEC Motors tab.
2. Press the button Check Locations.
3. Wait for the motor indexers to read out. The values in the right most column, underthe heading Indexer Sta... will update from top (A) to bottom (H).
11
3. Running CIRCE at the GTC
Figure 3.1. The CJEC Motors tab is used to query and position the mechanisms.
3.2 Datum the mechanisms
Datuming a mechanism tells the indexer to move the mechanism until a knocker onit triggers an associated snap action switch. The mechanism immediately stops, andundergoes a small ‘dance’ where it backs off of the switch and then re-datums at a lowerspeed, after which the indexer drives the mechanism back off the switch by a smallamount. The step count is then set to origin.
To datum,
1. Select the check box of mechanism,
2. Press the associated Datum button.
We generally datum only one or two mechanisms at a time.
Precautions
• Do not Datum the Window mechanism (as it moves to Open) if the differentialtemperature between the current temperature and the dew point temperature is> 4 ◦C.
12 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
3.3. Taking images
Notes
• The Window mechanism’s Datum position is at Open. The Window mechanism wasreplaced 03 March 2015. The new window cover is a rugged shutter (compared tothe iris mechanism it replaced). It has a travel range of ∼ 270 000 steps and takes∼45 seconds to close or open.
• Indexer A is ‘flakey’. While opening and closing the Window, we noticed (March2015) that sometimes the indexer claims the mechanism is moving; the step countchanges as expected. However, it moves well over 270 000 steps without hittinga limit switch. As the operator, you can check to see if the Window is moving bytaking 3 second exposures with the Ks filter:
1. If the Window is at Closed, start by moving FW1 to ‘Ks’. Take a 3s exposure(Single-Frame Mode) and send this frame to background in JDD; this will actas the Dark frame. Move the Window to open using the CJEC Motors tab.Take a set of 3s exposures (one at a time) to verify that the window is actuallymoving; the IR light from the telescope turret is more than adequate to indicateif the Window is actually moving.
2. Similiarly, if the Window is at Open, take a series of 3s Ks exposures in Single-Frame Mode to verify that the Window is closing. The Window shutter willblock enough IR light to be easily noticable if the Window is actually movingto closed.
• If the Window seems to be ‘stuck’, try increasing the run current to 75% viathe Display & Adjust Motor Parameters in the lower center of the CJECMotors tab. If that fails to work, try increasing the run current to 90%. Make sure tolower the run current to its nominal 50% after successfully moving the Window to Openor Closed.
3.3 Taking images
Images may be taken singly through either the CJEC Main tab (Figure 2.2, page 5) orthrough the JDD main window (see Figure 2.3, page 6). Sequences of images with CIRCEin different configurations, and with or without moving the telescope (i.e. ObservingSequences) may be executed from the CJEC Main tab.
3.3.1 Acquiring single images
Acquiring single frames is easy to do using the CJEC Main tab. Verify that the OBSERVESEQUENCE Input is set to ‘Single-Frame Mode’; if not, select ‘Single Frame Mode’ fromthe pull-down menu and hit the green Apply’ button in the lower left (see Figure 2.2).Configure th DETECTOR CONTROL (blue box) to the settings you want (exposure time isin milli-seconds, so a 3 second exposure requires 3000 in the Exp Time field), makingsure to press ‘Enter’ after changing any of the settings. Press the green ‘Apply’ buttonagain to send the new settings to the ISDEC.
Pressing the green ‘Observe’ button on the lower right will start the exposure. JDD,if already running, will automatically grab the frame as it becomes available (typically 2
circe_110_001_gtc_obs_guide; hg tag: 1.A 13 / 22
3. Running CIRCE at the GTC
– 3 seconds after the frame is written to disk). If JDD fails to load the latest frame, youcan use the light blue ‘Load Newest Image’ button on JDD to force it to grab the newestframe available.
3.3.2 Acquiring images using Observing Sequence files
Observing Sequence Pattern (XML) files1 may be selected and run from the CJEC Mainwindow; see the bottom left region in Figure 2.2 (page 5). These files may also be written tojust configure the instrument for exposures, such as for darks, flat fields, or gain-linearitycurves.
3.4 Focusing CIRCE
Focusing CIRCE should be done as soon as stars appear (after twilight flats). The Windowshould be at ‘Open,’ Filter Wheel 1 at the filter you’ll be using for science observa-tions, and the Lyot wheel should be at ‘Lyot.’
1. Using JDD, select a bright-ish star in the field (the first science field of the nightworks).
2. Offset the telescope using the Telescope Offset Control panel in JDD (see § 3.5 for aguide) by 10 or 20 arcseconds in your favorite direction (remember which directionyou chose so that you can undo the motion later!).
3. Ensure that you are using the filter you want to use for your science observations.
4. Take a short exposure (3 – 5 seconds).
5. Click on the Telescope Offset Control tab in JDD to open the Telescope Offset Controlpanel.
6. Note the current focus number (relative or absolute) for comparison
7. We have noticed that the focus should be driven to the LEFT (using positive valuesin the Focus increment field) when the star image appears to be stretched alonga ‘ y = -x’ line, and to the RIGHT (again, using positive values) when the star imageappears to be stretched along a ‘y = +x’ line.
8. Adjust the focus until the star image appears round.
9. Record the focus (one day we might have a good idea of what the focus should berelative to the focus for OSIRIS and CANARICAM, and thus be more efficient atswitching between instruments).
3.5 Using the Telescope Offset Control panel in JDD
JDD has a very nice tool for offsetting and centering the telescope called the TelescopeOffset Control panel. To access it, click on the Telescope Offset Control tab in JDD.A new window will pop up insert screenshot with three main parts.
1. For reference, these files are in the circe home space on the GTC machines (e.g. ormcon4), in\ufcirceinstall\etc\obsSequences\.
14 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
3.5. Using the Telescope Offset Control panel in JDD
Precautions when taking images
• During Engineering commissioning (2014-12-11) we saw several garbled images,due to USB transfer errors from the I-SDEC controller and circelcu. It is a goodidea to keep the CJEC Main tab in view, to watch the DAS status for ERROR, inaddition to watching the images as they are displayed in JDD.
circe_110_001_gtc_obs_guide; hg tag: 1.A 15 / 22
4 Daily actions with CIRCE
4.1 Dome closed
If the weather is bad enough during the night that the dome is periodically opened andclosed, move Window to Closed to prevent condensation.
4.2 End of night tasks
After deciding to stop observing for the night, please1. Move Window to Closed. Verify that the Window has indeed closed by taking a
few Ks exposures before and after closing
2. Park the Filter at Dark; from the CJEC Motors tab this moving [D]> FW1 toDark.
4.3 Useful reference information
• The array center of rotation during Science Commissioning (2015-03-04) was at(x, y) = (968.8, 982.2) in pixel coordinates.
• The CIRCE optical axis is at (x, y) = (943, 1003); for reference the detector center isat (1023.5, 1023.5).
• The array center of rotation during First Light (2014-12-10) was at (x, y) = (965.5, 975.3)in pixel coordinates.
This corresponds to a shift of (x, y) = (25, 21) pixel⇔ dx = 0.45 mm, dy = 0.38 mm.
17
5 CIRCE Trouble Shooting
5.1 General Items
Window fails to reach Closed
1. Abort2. Datum3. Re-move to Closed
Iterate. See also the notes on page 13. This procedure worked during Engineeringcommissioning within three iterations.
Mechanism positions are wrong or do not make senseIt is possible the mc agent has lost connection to the indexers via the Perle.
1. On the CJEC Motors tab press the green button at bottom right labeledRe-Connect MC agent to indexers.
2. Next, press the yellow button at the bottom middle labeled ConnectingSockets.... This will reopen the sockets between the panel and the agent.
If nothing response to clicks on the CJEC Motors tab
1. Ppress the yellow button at the bottom middle labeled Connecting Sockets....This will reopen the sockets between the panel and the agent.
19
6 Mechanism Operational ParametersDetails
This chapter will contain some low level details regarding the operation of various mech-anisms, including nominal parameters.
6.1 Window Mechanism
Notes from 12 June 2015 servicing
These notes are from S. S. Eikenberry.
6.1.1 Nominal mechanism indexer parameters
Initial Speed = 24
Term speed = 5036
Acceleration = 32
Deceleration = 32
Drive current = 25
Back Lash = 0
Datum speed = 5036
Final Speed = 100
Datum Direction = 0
Step resolution (D) = 1 = Full stepping1
Other key features of this mechanism to remember:
• Datum position = Open
• Moving from Open⇒ Closed : Move Positive Steps
• Moving from Closed⇒ Open : Move Negative Steps
• The nominal distance from Open to Closed = 222 024 steps.
1. Not 1/2 or 1/8 stepping.
21
6. Mechanism Operational Parameters Details
As noted above, the nominal distance from Open to Closed is 222 024 steps. How-ever, this is VERY nominal. In practice, once datumed, the Closed position seems torange from 199 to 850 steps greater than this (as of June 2015). This means that the trueClosed position is probably more like 222 550 steps from the datum location, and thereis a spread of at least ±350 steps around that value. The scatter seems to be smaller(< 100 steps) in a given gravity vector, but changing FC Rotator orientation shifts theoverall position by a few hundred steps. Note that this is < 1 mm overall shift, and iscompatible with expectations.
Note also that moving to Open is also systematically shifted from the datum location(even though datuming the window cover sets these to equal!). This is probably becausethe move to Open is a controlled move (including a rampdown), while datuming includesa fast move and a slow move into a limit switch — the nominal datum backlash is probablyinsufficient, creating the observed offset. This does NOT harm operations in any way —just a note of explanation.
As a result of this, sending the Window Cover to Open or Closed seldom ends withthe step count equalling the actual Open and Closed nominal step counts. As a result,the Named Position pulldown in CJEC will be colored yellow. This is normal for thewindow cover, and no need to worry.
As long the window cover datums properly, and moving to the Closed positionterminates in something like 222 500 steps (give or take 1 000 steps), the window cover isOK.
22 / 22 circe_110_001_gtc_obs_guide; hg tag: 1.A
